The present invention is directed to a method of adaptive knock control of an internal combustion engine and a corresponding device for performing the method of adaptive knock control.
There are already known internal combustion engines that operate with direct gasoline injection. For operation of these internal combustion engines, a distinction is made between operating modes such as homogeneous operation and stratified charge operation or homogeneous lean operation. In addition, a method and a corresponding device for adaptive knock control are known from published German Patent Application 195 32 504, where relevant firing angle retardation angles for knock control are stored in an adaptive engine characteristics map upon leaving an adaptive engine characteristics map range and are read out of the adaptive engine characteristics map under certain conditions. For the load operating parameter or the rotational speed operating parameter, the adaptive engine characteristics map is subdivided into ranges, each of which is assigned a firing angle retardation angle.
According an embodiment of the present invention an overwriting of the retardation angle of the adaptive engine characteristics map occurs during a change in operating modes and, due to the fact that the retardation values are read out of the specific engine characteristics map, the occurrence of unnecessary knocking or excessive retardation is prevented.
Six operating modes are currently differentiated and may also be differentiated to advantage with respect to adaptive knock control. In addition, the load and/or the rotational speed are selected as operating parameters on which the adaptive engine characteristics map values depend, because the firing angle and thus also the retardation angle are influenced primarily by these parameters. The adaptive engine characteristics maps are individually provided for each cylinder.